| 摘要 |
<p>The invention relates to an impingement drying unit for a dryer section of a paper or board machine, which comprises a drying group (R) and an impingement drying unit (10) which is placed above and/or below a row (DSR) of drying cylinders (3) and in which a paper or board web (2) has been arranged to be conducted past the impingement drying unit while supported by a drying fabric (1), such as a wire or equivalent. The invention is characterised in that the impingement drying unit (10) comprises at least one impingement surface (IP1, IP2) the side profile of which is straight, changeably curved in its radius of curvature, in the shape of a broken line or a selectable combination of these, and that the impingement surface or a tangent line to the impingement surface or a line passing via the beginning and the end of the impingement surface or an extension of said line forms on the impingement side an angle with a horizontal plane parallel to the machine level, which angle is ≤ 120°, advantageously in a range of 120° - 60°, most advantageously about 90°.</p> |
